This invention relates to novel 15.alpha.-sulfonyloxy-12.beta.-hydroxypregnanes and to a process for their production.
Only the 12.beta.,15.alpha.-diesters of 12.beta.,15.alpha.-dihydroxy-20-ketopregnanes are known in the literature, such as, for example, the 12.beta.,15.alpha.-diacetoxy-4-pregnene-3,20-dione (Helv. 41 [1958] 301; same 46 [1963] 889; or same 48 [1965] 1935), the 3.beta.,12.beta.,15.alpha.-triacetoxy-5.alpha.-pregnan-20-one, or the 7.beta.,12.beta., 15.alpha.-triacetoxy-5.alpha.-pregnane-3,20-dione (J. Chem. Soc. [1972] 2759). Partially esterified 12.beta.,15.alpha.-dihydroxy-20-ketopregnanes are not described.
The present invention is directed to the problem of providing intermediates useful in the digoxigenin synthesis by a partial esterification of 12.beta.,15.alpha.-dihydroxypregnanes wherein the 15.alpha.-hydroxy group is selectively esterified with an ester group which can be split off again under appropriate conditions with the formation of a .DELTA..sup.14 -double bond.